ABSTRACT Support is requested for a Keystone Symposia meeting entitled HIV Vaccines, organized by Drs. Andrew B. Ward, Penny L. Moore and Robin Shattock. The meeting will be held in Steamboat Springs, Colorado from March 26-30, 2017. Despite great progress in preventing and treating HIV, new infections continue to plague communities around the world, and the need for an HIV vaccine is as urgent as ever. Several large cohorts of HIV-infected individuals have enabled tremendous advances over the past five years in understanding immune responses to natural HIV infection. These advances have included the isolation of broad and potent anti-HIV antibodies, defining their developmental pathways, the generation of native-like Env trimers for immunization, and high-resolution structures of the envelope glycoprotein in complex with bnAbs. By 2017, many of these discoveries will have enabled new concepts to transition into human clinical trials, including passive monoclonal antibody therapy and novel immunization approaches. These platforms, incorporating improved technology for monitoring immune responses, will drive major advances in the vaccine field. This meeting will present the latest results from human clinical studies, along with the cutting-edge basic science behind such trials to highlight approaches that may lead to an HIV vaccine, and also reveal the molecular underpinnings of B and T cell-mediated immunity.